JP2016100605A - Solar cell module - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a solar cell module in which solar cells are connected to each other through a plurality of wiring members.SOLUTION: A solar cell module includes: a plurality of solar cells each including first electrodes 113 collecting first conductive charges and second electrodes collecting second conductive charges opposite the first conductive charges, the solar cells positioned adjacently to one another; and a plurality of wiring members 125 configured to electrically connect the first electrodes to the second electrodes of adjacent solar cells, the wiring members positioned in parallel with adjacent ones of the wiring members. The plurality of wiring members includes a first wiring member disposed in a corner area of a solar cell having a corner, and a second wiring member disposed in a non-corner area excluding the corner area.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a solar cell module in which solar cells are connected to each other with a plurality of wiring members.

  Recently, there is a growing interest in alternative energy to replace existing energy resources, such as oil and coal, as predicted. Among them, solar cells are attracting attention because they can use abundant energy resources as batteries that produce electric energy from solar energy and have no problem of environmental pollution.

  A general solar cell includes a substrate 110 and an emitter layer 120 made of semiconductors of different conductive types such as p-type and n-type, and an emitter layer 120 and a substrate 110 and an emitter portion 120, respectively. With connected electrodes. At this time, a pn junction is formed at the interface between the substrate 110 and the emitter section 120.

  When light enters such a solar cell, a plurality of electron-hole pairs are generated in the semiconductor, and the generated electron-hole pairs are separated into electrons and holes, respectively. Are collected in the direction of the n-type semiconductor and the p-type semiconductor, for example, in the direction of the emitter section 120 and the substrate, and collected by the electrodes electrically connected to the substrate 110 and the emitter section 120. And get power.

  The object of the present invention was created from such a technical background, and is to provide a new type of solar cell module.

  In a preferred embodiment, each of the solar cell modules includes a first electrode that collects a first conductive charge and a second electrode that collects a second conductive charge opposite to the first conductive charge. A plurality of solar cells arranged adjacent to each other, and a plurality of wiring members arranged in parallel to each other, electrically connected to the second electrode of the adjacent solar cell and the first electrode, The wiring material includes a first wiring material disposed in a corner region of the solar cell including a corner portion having a curved end, and a second wiring material disposed in a non-corner region of the solar cell excluding the corner region. Including.

  Preferably, the length of the first wiring material is shorter than the length of the second wiring material.

  Preferably, the total number of first electrodes and second electrodes connected to the first wiring material is less than the total number of first electrodes and second electrodes connected to the second wiring material.

  Preferably, the end of the first wiring member is separated from the corner portion by a first distance, and the end of the second wiring member is separated from the end of the solar cell by a second distance.

  Preferably, the first distance and the second distance are the same, and the first distance is smaller than the pitch of the first electrodes.

  Preferably, the first distance may be shorter than the second distance.

  Here, the first electrode may be located on a front surface of each of the plurality of solar cells, and the second electrode may be located on a rear surface of each of the plurality of solar cells.

  In addition, an electrode pad portion may be formed at a portion where the first electrode and the wiring material or the second electrode and the wiring material intersect.

  In addition, unlike the above, all of the first electrode and the second electrode can be located on the rear surface of each of the plurality of solar cells.

  In such a case, a conductive adhesive portion is formed at a portion where the plurality of wiring members electrically connected to the first electrode and the first electrode intersect, and the first electrode and the second electrode An insulating adhesive portion may be formed at a portion where the plurality of wiring materials electrically connected to each other intersect.

  The plurality of wiring members connected to the second electrode of the adjacent solar cell and the plurality of wiring members connected to the first electrode can be connected to each other via a connection bar, The connection bar may be located between solar cells adjacent to each other.

  The connection bar extends in a direction intersecting with a length direction of the plurality of wiring members connected to the second electrode and a length direction of the plurality of wiring members connected to the first electrode. be able to.

  Further, the non-corner region of the solar cell is located at the center of the semiconductor substrate of the solar cell, the corner regions of the solar cell are located on both sides of the non-corner region of the semiconductor substrate, and the length of the corner region is The length may be shorter than the length of the non-corner region.

  At this time, at least one wiring member connected to the first electrode and at least one wiring member connected to the second electrode may be located in the corner region.

  Each of the plurality of wiring members may be formed of a wire having a circular cross section or a ribbon having a rectangular cross section.

  The first electrode that is present between the end of the second wiring member and the end of the solar cell and is not connected to the first wiring member or the second wiring member is connected to the second wiring member by a connection bar. Can be connected to the first electrode.

  Preferably, the solar cell module includes a plurality of first pad portions where intersections of the first electrode and the first wiring member are arranged in the corner region, and the first electrode and the first in the non-corner region. A plurality of second pad portions disposed at intersections of the two wiring members, and an end of the first wiring member is an outermost pad located closest to an end of the solar cell among the plurality of first pad portions The end of the second wiring member is fixed to the outermost pad portion located closest to the end of the solar cell among the plurality of second pad portions.

  Preferably, the first outermost pad portion to which the first wiring material is fixed is separated from the corner portion by a third distance, and the second outermost pad portion to which the second wiring material is fixed is the A fourth distance away from the edge of the solar cell.

  Preferably, the third distance and the fourth distance are the same, and the third distance and the fourth distance are each 5-15 (mm).

  Preferably, the third distance is shorter than the fourth distance, and the first outermost pad portion and the second outermost pad portion are located on the same line based on the extending direction of the first electrode.

  Preferably, the plurality of first pad portions and the plurality of second pad portions are connected to each other by a plurality of connection electrodes.

  Preferably, the connection electrode is connected to all of the first electrodes existing in each of the corner region and the non-corner region.

  Preferably, the connection electrode connects at least one or more first electrodes existing between the outermost pad portion and an end of the solar cell to the outermost pad portion.

  Preferably, the solar cell module is configured to extend in a diagonal direction, and at least one first electrode existing between the outermost pad portion and an end of the solar cell is provided on the outermost pad portion. A link electrode to be connected is included.

  Preferably, the number of the second wiring members is at least five times greater than the number of the first wiring members.

  Preferably, each of the plurality of wiring members has the total number of the plurality of wiring members positioned at the center of each region partitioned by the width of the solar cell.

  In one embodiment of the present invention, a wiring member is also arranged in the corner portion of the solar cell including the corner portion so that charges can be collected uniformly in the entire solar cell.

  In one embodiment of the present invention, the length of the plurality of wiring members arranged in the corner region is shorter than the length of the plurality of wiring members arranged in the non-corner region, and the plurality of wiring members are arranged at the corner portion. Solve the problem of short circuit.

  In one embodiment of the present invention, when a solar cell module is manufactured by adjusting the length of a plurality of wiring members arranged in a non-corner region to the corner region, all the plurality of wirings are performed in a single cutting step. Allow the material to be cut.

  In one embodiment of the present invention, in a solar cell including a corner portion, a wiring material is also arranged at the corner portion so that charges can be collected uniformly throughout the solar cell.

  In one embodiment of the present invention, the length of the wiring material arranged in the corner region is made shorter than the length of the wiring material arranged in the non-corner region, thereby solving the problem of short-circuiting the wiring materials at the corner portion.

  In one embodiment of the present invention, when a solar cell module is manufactured by matching the length of the wiring material arranged in the non-corner region with the corner region, all the wiring materials can be cut in a single cutting step. Like that.

It is a figure which shows the mode of the whole solar cell module by the Example of this invention. It is a figure which shows the cross-sectional mode along the AA line direction of FIG. It is a figure which shows the cross-sectional mode along the BB line direction of FIG. It is a figure which shows the mode of a wiring material. It is a figure for demonstrating the corner part of a solar cell. It is a figure which expands and shows the corner part of a solar cell. It is a figure for demonstrating where a wiring material is located in a solar cell. It is a figure for demonstrating the problem which wiring materials of a solar cell short-circuit. It is a figure which shows the plane state of the solar cell which concerns on the 1st Embodiment of this invention. It is a figure which shows the plane state in which the solar cell shown in FIG. 9 was connected by the wiring material. It is a figure which expands and shows a corner part selectively in two adjacent solar cells. It is a figure which shows the cross-sectional mode along CC line of FIG. It is a figure which shows a mode that the edge of a 1st wiring material and the edge of a 2nd wiring material are located on the same line. It is a figure which shows the plane state of the solar cell which concerns on the 2nd Embodiment of this invention. It is a figure which shows the plane state in which the solar cell shown in FIG. 14 was connected by the wiring material. It is a figure which shows the plane state of the solar cell which concerns on the 3rd Embodiment of this invention. It is a figure which shows the plane state in which the solar cell shown in FIG. 16 was connected by the wiring material. It is a figure which shows the plane state of the solar cell which concerns on the 4th Embodiment of this invention. It is a figure which shows the plane state in which the solar cell shown in FIG. 18 was connected by the wiring material. In other embodiment of this invention, it is a figure which shows the whole mode of the solar cell module comprised using the back surface contact type solar cell. It is a figure which shows the cross-sectional mode of the solar cell shown in FIG. It is a figure which shows a mode that two adjacent solar cells are connected by a connector. It is a figure which shows the mode of the plane where two adjacent solar cells in the solar cell module of FIG. 20 were connected by the wiring material. FIG. 24 is an enlarged view of a part of the front surface of the solar cell module described in FIG. 22, and FIG. 24 is an enlarged view of a part of the rear surface of the solar cell module described in FIG.

  The drawings attached to this specification show a schematic diagram for easy explanation of the invention. Therefore, the attached drawings may be different from actual ones.

  Embodiment described below is only a preferable form, and does not show all this invention. In particular, an embodiment created by selectively selecting each component described through the following embodiments and combining them is also described above. Therefore, this also belongs to the present invention.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the description, the same or corresponding parts are denoted by the same reference numerals in the drawings, and the description will not be repeated in order to avoid duplication of description.

  Hereinafter, a solar cell module according to an embodiment of the present invention will be described with reference to FIGS. 1 shows the overall state of the solar cell module, FIG. 2 shows a cross section along the AA line direction of FIG. 1, FIG. 3 shows a cross section along the BB line direction of FIG. The state of the wiring material is shown.

  In the solar cell module of this embodiment as shown in FIGS. 1 to 4, a plurality of wiring members 125 having a thin line width are connected to a plurality of solar cells (C1-C3) arranged adjacent to each other. doing. The wiring member 125 is physically and electrically connected to the front electrode 113 formed on any one of the two adjacent solar cells, and the rear electrode 115 formed on the other rear surface. Connected physically and electrically. The wiring member 125 is connected to the front electrode 113 and the rear electrode 115 of the two solar cells adjacent to each other as described above to electrically connect the two solar cells.

  In this embodiment, the solar cell is described as having a front-side electrode 113 and a rear-side electrode 115 arranged in the same shape with a bifacial structure that absorbs light from the front and rear surfaces of the semiconductor substrate 111, respectively. . The following embodiment is merely an example, and can be realized in the same manner for solar cells of all known structures unless there is a special limitation.

  The solar cell has a polyhedron shape having a thin thickness, the horizontal and vertical sizes are about 156 (mm) * 156 (mm), and the thickness is 150 (μm) −250 (μm). is there.

  A front electrode 113 is located on the front surface on which light is incident and is connected to the wiring member 125. The front electrode 113 collects conductive charges that are opposite to the semiconductor substrate 111. In one example, if the semiconductor substrate 111 is a p-type semiconductor substrate, the front electrode 113 collects electrons.

  The semiconductor substrate 111 has a pn junction and includes a first conductive impurity and is made of an n-type or p-type semiconductor substrate.

  On the rear surface of the semiconductor substrate 111, a rear electrode 115 having a form similar to that of the front electrode 113 is formed. The rear electrode 115 collects conductive charges that are opposite to the front electrode 113.

  Between the semiconductor substrate 111 and the front electrode 113, between the semiconductor substrate 111 and the rear electrode 115, an emitter layer doped with impurities at a high concentration, a rear electric field portion, and prevention or suppression of recombination of charges from the surface. There is a passivation film.

  In the solar cell having such a configuration, two adjacent solar cells are connected by the wiring member 125, and the wiring member 125 includes the front electrode 113 formed on the front surface and the rear surface of the two adjacent solar cells, respectively. It is electrically connected to the rear electrode 115.

  On the other hand, in this embodiment, each solar cell (C1-C3) includes a corner portion 111a having a corner formed as a part of a circle. As an example, a similar type wafer (pseudo type wafer) includes the corner portion 111a in this way for reasons of the manufacturing process, and a solar cell manufactured using this pseudo-type wafer is as in this embodiment. The corner portion 111a is provided.

  In this embodiment, the wiring member 125 has a plurality of second wirings positioned between the first wiring member 125a and the pair of first wiring members 125a arranged so as to cross the corner portion 111a according to the position. The wiring material 125b is included.

  The first wiring member 125a is located on the outermost side among the plurality of wiring members connecting the two adjacent solar cells, and the plurality of second wiring members 125b are positioned between these corners. Two adjacent solar cells are connected without crossing the portion 111a. The first wiring member 125a, the second wiring member 125b, and the second wiring member are separated from each other at a constant interval, and form a stripe arrangement.

  The wiring member 125 has a wire shape as illustrated in FIG. 4B shows a cross-sectional shape of the wiring member 125. FIG.

  As shown, the wiring member 125 has a circular cross-sectional state in which the coating layer 125a coats the core layer 125b with a thin thickness (inside and outside of 12 (μm)), and the whole is 250 (μm) −500 (μm). Having a thickness of However, the wiring member 125 may have a ribbon shape having a rectangular cross section, and thus the wiring member 125 having a ribbon shape having a rectangular cross section may have a width of 0.5 mm to 2 mm. It can be between.

  The core layer 125b is a metal material with good conductivity such as Ni, Cu, Ag, Al, and the coating layer 125b has a chemical formula such as Pb, Sn or SnIn, SnBi, SnPb, Sn, SnCuAg, SnCu. The wiring material 125 can be connected to the electrodes (113, 115) through soldering that includes a metal substance, particularly solder, and melts and bonds the base material.

  When connecting two adjacent solar cells, when the semiconductor substrate has a size of 156 (mm) * 156 (mm), 10-18 pieces are used. The substrate size, electrode line width, thickness, pitch, and the like are adjusted as variables.

  The above description is based on the wire member 125 having a wire shape with a circular cross section, but the cross section can have various shapes such as a rectangle and an ellipse.

  Such a wiring member 125 electrically connects two adjacent solar cells, one is connected to the front electrode 113 of the first solar cell (C1), and the other is the second solar cell ( C2) connected to the rear electrode 115. Moreover, the wiring member 125 connects these also between a 2nd solar cell (C2) and a 3rd solar cell (C3), and one side is connected to the front electrode 113 of a 2nd solar cell (C2), The other is connected to the rear electrode 115 of the third solar cell (C3). Thereby, the 1st-3rd solar cell (C1-C3) is mutually electrically connected by the wiring material 125, and the wiring material 125 is located in the front surface and the back surface based on one solar cell, respectively. .

  One preferable mode for connecting the electrode and the wiring material is soldering for melting and bonding the base material. However, this step is not essential.

  In this embodiment, a pad portion 140 can be selectively formed at a point where the front electrode 113 and the wiring material 125 intersect. The pad portion 140 widens the area where the front electrode 113 and the wiring material 125 intersect, reduces the contact resistance when the wiring material 125 is connected to the front electrode 113, and increases the coupling force between the wiring material 125 and the front electrode 113. As a result, the charge is often transferred from the front electrode 113 to the wiring member 125.

  On the other hand, when the front electrode 113 and the wiring member 125 are soldered, the wiring member 125 is positioned on the front and rear surfaces of two adjacent solar cells, respectively, and the wiring member 125 is opposed to the front electrode 113 and the rear electrode 115, respectively. In this state, the coating layer 125a of the wiring member 125 is heated at a melting temperature or higher for several seconds. As a result, the wiring material 125 is attached to the electrodes while the coating layer 125a is melted and cooled.

  In this embodiment, the wiring material 125 is soldered via the front electrode 113 and the pad portion 140, and the wiring material 125 is directly melt-bonded to the front electrode 113 even at the intersection where the pad portion 140 is not present. The contact resistance between the electrode and the wiring material can be reduced, the cell efficiency can be increased, and the coupling strength of the wiring material can also be increased.

  In an alternative example, the wiring material 125 may be attached to the electrode with a conductive adhesive. The conductive adhesive is made of epoxy (epoxy) -based synthetic resin or silicon-based synthetic resin with conductive particles expressed as Ni, Al, Ag, Cu, Pb, Sn, SnIn, SnBi, SnPb, Sn, SnCuAg, SnCu. It is a substance that contains conductive particles) or solder, and is a substance that is thermally cured when heated in liquid form. In addition, the wiring material 125 can adhere to the solder paste on the electrodes. The solder paste is a paste containing solder particles such as lead (Pb) or tin (Sn). When heat is applied above the melting temperature, the two base materials melt while the solder particles present in the solder paste melt. Combine.

  In this embodiment, the front electrode 113 is directly connected to the wiring member 125 as described above, instead of including a bus electrode having a wide line width as in the prior art. Accordingly, since the bus electrode can be omitted, the manufacturing cost can be reduced, and the bus electrode formed over a wide area on the light receiving surface can be omitted, so that the light receiving efficiency can be reduced accordingly. As a result, the efficiency of the solar cell can be improved.

  In this embodiment, since the solar cell has a double-sided light receiving structure, the rear electrode is different from the front electrode described above only by the pitch between the electrodes, and the rest is the same. is there. Therefore, the description of the front electrode is substituted for the rear electrode.

  Hereinafter, the corner portion 111a of the solar cell 100 constituting the solar cell module as described above will be described in detail with reference to FIGS. FIG. 5 is a view for explaining a corner portion of the solar cell, and FIG. 6 is an enlarged view of the corner portion.

  The solar cell 100 as illustrated in FIGS. 5 and 6 has an approximately square planar shape having the same horizontal and vertical dimensions. Since the size of the substrate 111 most widely used in the current market is 156 (mm) * 156 (mm), the following description is based on this. Any size substrate can be used.

  In a solar cell having a horizontal * longitudinal size of 156 (mm), each corner portion 111a is performed as a part of a circle having a radius (r) of 100-104 (mm). In this case, the horizontal length (x) of the corner portion 111a is about 11-13 (mm). Since the vertical length (y) of the corner portion 111a is the same as the horizontal length, the vertical length (y) is also about 11-13 (mm).

  Therefore, the length (y) in the vertical direction of the substrate from the corner portion 111a can be shortened by a maximum of 22 (mm) -26 (mm) from the overall vertical length of the substrate, 156 (mm). Therefore, the corner portion 111a includes a curved portion or a curved end. However, when each of the corner portions 111a includes a straight end, the curved portion or the curved end is not necessary. Furthermore, based on the shape of the corner portion 111a, the semiconductor substrate 111 may be a polygon such as an octagon.

  On the other hand, when the solar cells adjacent to each other are connected by a plurality of wiring members 125 as in this embodiment, the wiring members 125 are used to efficiently collect and transmit the charges generated by the solar cells. , As illustrated in FIG.

  In FIG. 7, a case where solar cells adjacent to each other with 12 wiring members are connected will be described as an example.

  In FIG. 7, it is desirable that a plurality of wiring members collect and transmit the charges generated from the solar cell 100 uniformly, and therefore, the wiring members must be arranged uniformly throughout the solar cell. Therefore, when the horizontal length of the solar cell 100 is divided into 12 equal parts, the wiring member is positioned at the center of each divided area.

  In the figure, “Cl” is a dividing line that divides the solar cell 100 into 12 equal parts, and “Bp” indicates a center line of each divided area. Among these, the wiring member is positioned in alignment with the center line (Bp), and electrically connects two adjacent solar cells.

  Here, since the distance (Ep) from the dividing line (Cl) is “lateral length of solar cell / 12”, it is 13 (mm), and the lateral length of the corner portion 111a is 11-13. (Mm) and larger than Ep / 2. Therefore, the 1st wiring material 125a located in the outermost outline among the several wiring materials arrange | positioned at a solar cell will be located so that the corner part 111a may be crossed.

  In other words, when the following Equation 1 is satisfied, the first wiring member 125a is positioned so as to cross the corner portion 111a.

[Formula 1]
Horizontal length of corner (Cp)> (width of solar cell / number of wiring materials) / 2

  Then, when the solar cell 100 is equally divided into 12 and the wiring material is arranged at the center thereof, the distance (t) from the tip of the solar cell 100 to the wiring material is (the horizontal length of the solar cell / wiring material). Number) / 2.

  On the other hand, as described above, the vertical length (y) of the solar cell at the corner portion 111a can be made 22 (mm) -26 (mm) shorter than the overall vertical length of 156 (mm). Accordingly, the length of the wiring material arranged in the corner regions (AC1, AC2) including the corner portion 111a is the same as the length of the wiring material arranged in the non-corner region (AT) where there is no corner portion 111a. Then, in the case of the wiring material located in the corner region, it is exposed outside the solar cell 100 by the corner portion 111a.

  By the way, as illustrated in FIG. 8, the wiring material connects the front electrode and the rear electrode of two adjacent solar cells (CE1, CE2), and the wiring material is based on one solar cell. And are located on the back. Moreover, these (125UP, 125DW) which are each located in the front surface and the rear surface are located on the same line. Therefore, when the wiring material is exposed from the corner portion 111a, there arises a problem that a short circuit occurs with another wiring material facing the exposed wiring material on the same line.

  In this embodiment, in consideration of such problems, the wiring member is wired to the solar cell as follows to solve the above-described problems.

  FIG. 9 shows a plan view of the solar cell according to the first embodiment of the present invention, and FIG. 10 shows a plan view of the solar cell shown in FIG. 9 connected by a wiring material.

  9 and 10, a front electrode 113 is formed on the front surface of the solar cell 100.

  The front electrode 113 has a thin line width, extends long in one direction, and is arranged in parallel with adjacent ones to form a stripe arrangement. The front electrode 113 has a line width of 40 (μm) -100 (μm), a thickness of 15 (μm) -30 (μm), and a pitch (p) which is a distance between the electrodes is 1. .3 (mm) -1.9 (mm).

  The front electrode 113 of this embodiment has such a thin line width, whereas there is no conventional bus electrode. Therefore, when the front electrode 113 is connected to the wiring member 125, the contact area between the two is small and not only charge transport is difficult, but it is also difficult to connect the two electrically and physically.

  Considering this point, the front electrode 113 further includes a pad portion 140.

  The pad portion 140 is preferably arranged at an intersection where the wiring material 125 and the front electrode 113 intersect, and is formed for every n lines (n = natural number) in the length direction of the wiring material. In the drawing, the pad portion 140 is formed every five lines.

  The number of pad portions 140 is determined in consideration of variables such as size, electrode thickness, and pitch.

  The pad part 140 and the front electrode 113 can be formed simultaneously by screen printing in the same process, or can be separately formed in other processes.

  Although the above description was based on the front electrode 113, the solar cell of this embodiment is a double-sided light receiving solar cell, and the rear electrode 115 is also formed in the same shape as the front electrode 113, so that the rear surface Detailed description of the electrode 115 is omitted.

  The wiring member 125 connects two solar cells (CE1, CE2) adjacent to each other in the direction intersecting with the front electrode 113 formed as described above.

  In this embodiment, as described with reference to FIG. 7, the wiring member 125 is located at the center of each region divided by the number of wiring members, and includes a corner region (AC1, AC2) and a non-corner region (AT ) Is located in each.

  Specifically, the non-corner region (AT) of the solar cell is located at the center of the semiconductor substrate, and the corner regions (AC1, AC2) of the solar cell are defined by the non-corner region (AT) of the semiconductor substrate. The corner regions (AC1 and AC2) may be shorter than the non-corner region (AT).

  At this time, a wiring material connected to the first electrode 113 and a wiring material connected to the second electrode 115 may be located in the corner regions (AC1, AC2).

  Under the conditions described above, a total of twelve wiring members 125 are arranged, and the first wiring member 125a is positioned in the corner regions (AC1, AC2), and the second wiring member 125b is positioned in the non-corner region 125b. To do. One wiring member is located in each of the corner regions (AC1, AC2), and a total of ten second wiring members 125b are located in the non-corner region 125b. The wiring members are separated from each other by a certain distance, and are extended long in one direction so as to be parallel to the adjacent ones, thereby forming a stripe arrangement.

  The first wiring member 125a connects two solar cells (CE1, CE2) adjacent to each other in the corner regions (AC1, AC2) including the corner portion 111a, and the second wiring member 125b is compared with this. Connects two adjacent solar cells (CE1, CE2) in a non-corner region (AT) having no corner portion.

  One of the first wiring members 125a is located on the front surface of the first solar cell (CE1) and connected to the front electrode, and the other is located on the rear surface of the second solar cell (CE2) and the rear electrode. Connected with. In addition, one end 125a ′ of the first wiring member 125a is adjacent to the lower corner portion (111a_dw) on the rear surface of the first solar cell (CE1), and the other end (125a ″) is the second solar cell (CE1). Two solar cells (CE1, CE2) are connected to be positioned adjacent to the upper corner portion (111a_up) from the front surface of the battery (CE2).

  Similarly to the first wiring member 125a, the second wiring member 125b is located on the front surface of the first solar cell (CE1) and connected to the front electrode, and the other is connected to the second solar cell (CE1). CE2) Located on the rear surface and connected to the rear electrode. The end (125b ′) of the second wiring member 125b is adjacent to the support (CE11) of the first solar cell (CE1), and the other end (125b ″) is the upper end of the second solar cell (CE2). The two solar cells (CE1, CE2) are connected in a state adjacent to (CE21) Therefore, in this embodiment, the total length of the first wiring member 125a is determined by the corner portion 111 and the second wiring member 125b. The end of the first wiring member 125a and the end of the second wiring member 125b are shifted by “Sf”. The shift distance (Sf) is smaller than the width of the corner portion 111a (the length in the length direction of the wiring material).

  Thus, in this embodiment, since the total length of the first wiring member 125a is shorter than the total length of the second wiring member, the total number of front and rear electrodes connected to the first wiring member 125a is also the first number. It is less than the total number of front electrodes and rear electrodes connected to the two wiring members 125b.

  Hereinafter, with reference to FIG. 11 and FIG. 12, the wiring material arranged in the corner portion will be described in more detail. FIG. 11 shows a corner portion selectively enlarged by two adjacent solar cells, and FIG. 12 shows a cross-sectional view taken along the line CC in FIG.

  In the first solar cell (CE1) as shown, the end (E1) of the first wiring member 125a is separated from the corner portion 111a1 by the first distance (d1), and the end (E2) of the second wiring member 125b. ) Is separated from the end (CE11) of the first solar cell (CE1) by a second distance (d2).

  Preferably, in the non-corner region (AT), the end (E2) of the second wiring member 125b is located between the end (CE11) of the first solar cell (CE1) and the front electrode 113e directly adjacent thereto. Yes.

  If the end (E2) of the second wiring member 125b is positioned in front of the end (CE11) of the first solar cell (CE1) and placed between the two solar cells (CE1, CE2), as shown in FIG. It is possible that the wiring materials facing each other with the solar cell in between are short-circuited. When the end (E2) of the second wiring member 125b is behind the last front electrode 113e, the last front electrode 113e is not connected to the second wiring member 125b, so that the charge collected from the last front electrode 113e is reduced. The efficiency that cannot be passed to the second wiring member 125b may decrease.

  Similarly, since the first wiring member 125a is also separated from the corner portion 111a1 by the first distance (d1), it is possible to prevent short-circuiting with the other first wiring member 125a facing each other across the solar cell. .

  Thus, in this embodiment, the first wiring member 125a is located at a certain distance (d1) from the corner portion 111a1, and as described above, the first wiring member 125a is placed above and below the solar cell by the corner portion 111a. The problem that the first wiring member 125a located can be short-circuited can be solved.

  By the way, when the first wiring member 125a is separated by a certain distance (d1) at the corner portion 111a1, the end (E1) of the first wiring member 125a and the first solar cell (CE1) are separated by the corner portion 11. ) Between the front electrode and the front electrode (CE11). Thereby, the charge collection may not be improved, but in this embodiment, the second wiring material 125b directly adjacent to the first wiring material 125a is arranged so as to be connected to all the front electrodes 113, These problems are solved.

  On the other hand, in this embodiment, the first wiring material 125a is separated from the corner portion 111a1 by the first distance (d1), and the second wiring material 125b is separated from the end (CE11) of the first solar cell (CE1). It is separated by a second distance (d2). Therefore, the end (E1) of the first wiring member 125a and the end (E2) of the second wiring member 125b are not located on the same line.

  In a preferred embodiment, the first distance (d1) and the second distance (d2) are the same. The second distance (d2) is preferably smaller than the pitch (p) of the front electrodes 113. If the second distance (d2) is greater than the pitch (p), the second wiring member 125b may not be electrically connected to the last front electrode 113e.

  In the same manner, the first wiring member 125a, whose first distance (d1) should also be smaller than the pitch (p) of the front electrodes 113, can be connected to as many front electrodes 113 as possible.

  The first wiring member 125a is located in the corner area (AC1), and the number of front electrodes 113 connected to the first wiring member 125a is the number of front electrodes 113 connected to the second wiring member 125b. Smaller than.

  On the other hand, FIG. 13 shows a state where the end (E1) of the first wiring member 125a and the end (E2) of the second wiring member 125b are located on the same line. Thus, when the end (E1) of the first wiring member 125a and the end (E2) of the second wiring member 125b are located on the same line, there is an advantage that the manufacturing process can be simplified. As described above, since the end (E1) of the first wiring member 125a and the end (E2) of the second wiring member 125b are not on the same line, the first wiring member 125a and the second wiring member 125b should be cut separately. However, when the end (E1) of the first wiring member 125a and the end (E2) of the second wiring member 125b are located on the same line, the first wiring member 125a and the second wiring member 125b are cut together. be able to.

  Since the end (E1) of the first wiring member 125a and the end (E2) of the second wiring member 125b as illustrated in FIG. 13 are located on the same line, the fourth front electrode 113c The distance (Pd) protruding to the ends (E1, E2) is the same for the first wiring member 125a and the second wiring member 125b.

  The end (E1) of the first wiring member 125a is separated from the corner portion 111a1 by a third distance (d3), and the end (E2) of the second wiring member 125 is the end (CE11) of the second solar cell (C2). ) By the fourth distance (d4). While the end (E1) of the first wiring member 125a and the end (E2) of the second wiring member 125b are located on the same line, the third distance (d3) is determined by the corner portion 111a1 where the first wiring member 125a is located. Shorter than the fourth distance (d4).

  On the other hand, as in this embodiment, when the end (E2) of the second wiring member 125b is positioned in alignment with the end (E1) of the first wiring member 125a, there is a front electrode that is not connected to the second wiring member 125b. To do. However, when the front electrode is not connected to the wiring material in this way, the charge collected by the front electrode is not transmitted to the wiring material, and the efficiency of the solar cell may be reduced.

  In the present invention, in consideration of such a point, an electrode that is not connected to the wiring material is connected to another electrode that is connected to the wiring material by shifting the second wiring material 125b, thereby solving such a problem.

  In this embodiment, a connection bar 114 that electrically connects the last front electrode 113e and the fourth front electrode 113c is included.

  By this connection bar 114, the front electrodes existing between the last front electrode 113e not connected to the second wiring member 125b and the fourth front electrode 113c are connected to each other, and the fourth front electrode 113c is connected to the wiring Since it is connected to the material, the front electrode that was not directly connected to the wiring material is also connected to the wiring material.

  In this embodiment, the connection bar 114 may be configured as part of the front electrode 113 or may be independent of the electrode. As an example, the connection bar 114 may be made of the wiring material 125, and in this case, the connection bar 114 is formed together when the wiring material 125 is soldered to the front electrode 113.

  The number of connection bars 114 may increase or decrease in proportion to the number of electrodes that are not connected to the wiring material. For example, as the number of electrodes that are not connected to the wiring material increases, the number of connection bars 114 also increases in proportion thereto.

  FIG. 14 shows a plan view of the solar cell according to the second embodiment of the present invention, and FIG. 15 shows a plan view of the solar cell shown in FIG. 14 connected by a wiring material.

  14 and 15, a front electrode 113 and a connection electrode 116 are formed on the front surface of the solar cell 100.

  Similar to the first embodiment, the front electrode 113 has a thin line width, is extended long in one direction, and is arranged in parallel with adjacent ones to form a stripe arrangement. ing. The front electrode 113 has a line width of 40 (μm) -100 (μm), a thickness of 15 (μm) -30 (μm), and a pitch (p) which is a distance between the electrodes is 1. .3 (mm) -1.9 (mm).

  Similarly to the front electrode 113, the connection electrode 116 has a thin line width and extends long in a direction intersecting the front electrode 113, thereby electrically and physically connecting the front electrode 113.

  In a preferred embodiment, the connection electrode 116 has a line width of 40 (μm) -100 (μm) and a thickness of 15 (μm) -30 (μm), like the front electrode 113.

  Such a connection electrode 116 is located corresponding to where the wiring material is located, and connects the front electrode 113 that intersects the wiring material. In this embodiment, there are one connection electrode 116 in each corner region (AC1, AC2) and ten non-corner regions (AT), as in the case of the wiring material.

  The connection electrode 116b located in the corner region electrically and physically connects the front electrode 113 existing in the corner region (AC1, AC2), and the connection electrode 116a located in the non-corner region (AT) The front electrode 113 existing in the corner area (AT) is electrically and physically connected. Thus, the front electrode 113 is connected to each other by the connection electrode 116 in the corner region and the non-corner region.

  In this embodiment, the connection electrode 116 is formed in this way, the front electrode is connected, and at the position corresponding to the wiring material, the coupling force between the wiring material and the electrode is increased, while the front surface is The charge collected by the electrode 113 is transmitted well to the wiring member 125.

  In one example, the wiring material 125 is fixed to the pad portion 140 by soldering. However, the wiring material 125 is positioned facing the connection electrode 116 and is also soldered to the connection electrode 116. The bond strength between the material and the electrode is increased.

  Also in this embodiment, the pad portion 140 is formed along the intersection where the front electrode 113 and the connection electrode 116 intersect.

  The pad 140 widens the area where the front electrode 113 and the wiring material 125 intersect, reduces the contact resistance when the wiring material 125 is connected to the front electrode 113, and the charge collected by the front electrode 113 is well transmitted to the wiring material 125. In this way, the coupling force between the wiring member 125 and the front electrode 113 is increased.

  The pad portion 140 is desirably formed at every intersection in the length direction of the wiring member. However, in such a case, there is a problem that the light receiving area is reduced and the manufacturing cost is increased. In consideration of such points, in this embodiment, it is exemplified that the pad portion 140 is formed every five lines. The number of pad portions is determined in consideration of the charge collection efficiency, the size of the pad portion, the bonding force between the wiring material and the electrode, and the like.

  Such pad portions 140 are connected to each other by the connection electrode 116 described above.

  Based on the length direction of the connection electrode 116, the first and second outermost pad portions (140a, 140b) located closest to the end (Ced) of the solar cell are separated by a certain distance at the end (CE) of the solar cell. Is located.

  The first and second outermost pad portions (140a, 140b) arranged in the corner regions (AC1, AC2) are located at a first distance (dq1) from the end of the solar cell by the corner portion 111a. In other words, the first and second outermost pad portions (140a, 140b) disposed in the non-corner area (AT) are separated by a second distance (dq2) that is farther than the first distance (dq1).

  In this embodiment, it is preferable that the outermost pad portions (140a, 140b) are formed at the same positions as those adjacent to each other as illustrated in the figure.

  In addition, the tips of all the wiring members 125 are fixed to the outermost pad portions (140a, 140b). If the positions of the outermost pad portions (140a, 140b) are different, the wiring members are cut. In this case, the wiring members 125 should be cut, but if they are in the same position as adjacent ones as in this embodiment, all the wiring members 125 can be cut at a time, so that the manufacturing cost and time are reduced. Can be reduced.

  The above description is based on the front electrode 113 and the connection electrode 116 formed on the front surface of the solar cell. However, the solar cell of this embodiment is a double-sided solar cell, and the rear electrode 115 is also a front electrode. Since the connection electrode and the pad portion are formed in the same manner as described above, the detailed description thereof is omitted.

  The first and first wiring members (125a, 125b) as illustrated in FIG. 15 are respectively connected to the front electrode and the rear electrode of two adjacent solar cells, and these are electrically and physically connected. .

  One end (125a_ed1) of the first wiring member 125a is connected to the second outermost pad portion (140b ′) formed on the rear surface of the first solar cell (CE1), and the other end (125a_ed2). Are connected according to the first outermost pad portion 140a formed on the front surface of the second solar cell (CE2).

  When the first wiring member 125a is connected to the outermost pad portions (140a, 140b) in this way, the front electrode 113 and the first electrode existing between the outermost pad portions (140a, 140b) and the corner portion 111a. 1 The wiring material 125a is not connected, and the efficiency of the solar cell may decrease. However, in this embodiment, the front electrode 113 existing between the outermost pad portions (140a, 140b) and the end of the solar cell is connected to the outermost pad portions (140a, 140b) by the connection electrodes 116. It solves or suppresses the problems mentioned above.

  Similarly to the first wiring member 125a, the end of the second wiring member 125b is connected to the outermost pad portion (140a, 140b ′), and the connection electrode 116 is connected to the outermost pad portion (140a, 140b). ) And the end of the solar cell, the front electrode 113 is formed so as to be connected.

  As described above, the ends of the first and second wiring members are connected to the outermost pad portions, respectively, and the first and second wiring members remain at a certain distance from the respective corner portions and the ends of the solar cells. , And fixed to the first and second solar cells (CE1, CE2), respectively. Therefore, the problem that the two wiring members facing each other across the solar cell overlap as shown in FIG. 8 may be solved. Moreover, since the tip of the wiring material 125 is fixed to the pad portion 140, the end of the wiring material can be firmly fixed, and the problem that occurs at the tip of the wiring material can be solved.

  FIG. 16 shows a plan view of a solar cell according to the third embodiment of the present invention, and FIG. 17 shows a plan view in which the solar cells shown in FIG. 16 are connected by a wiring material.

  In FIG.16 and FIG.17, the solar cell of 3rd Embodiment exists between the 1st and 2nd outermost pad part from the edge of a solar cell compared with 2nd Embodiment. The only difference is that the front electrode is connected by a link electrode (Lk).

  In this embodiment, the connection electrode 116 ′ exists between the first outermost pad portion 140 a and the second outermost pad portion 140 b and connects the front electrodes 113 positioned between them to each other. ing.

  The front electrode 113, which exists between the first and second outermost pad portions (140a, 140b) and the end of the solar cell, is connected to the first and second outermost pad portions (Lk) by the link electrode (Lk). 140a and 140b) are electrically and physically connected respectively.

  The link electrode (LK) extends in the oblique direction toward the end (Ed) of the solar cell at the first and second outermost pad portions (140a, 140b). The link electrodes (LK) are paired and are symmetric with respect to the wiring material 125.

  There is no front electrode between the link electrodes (LK), and the front electrode 113 is “V” -shaped toward the end (Ced) of the solar cell in each of the first and second outermost pad portions (140a, 140b). It has a groove shape dug.

  In this embodiment, the front electrode, which exists between each of the first and second outermost pad portions 140a and the end of the solar cell, is physically and electrically connected with the link electrode (LK) in this way. I am letting. Such a link electrode (LK) is configured as a part of the front electrode 113.

  FIG. 18 shows a plan view of the solar cell according to the fourth embodiment of the present invention, and FIG. 19 shows a plan view of the solar cell shown in FIG. 18 connected by a wiring material.

  In FIG.18 and FIG.19, the solar cell of 4th Embodiment has a difference only in the position of a 1st and 2nd outermost pad part compared with 3rd Embodiment.

  The first and second outermost pad portions (140a1, 140b1) arranged in the corner regions (AC1, AC2) are located away from the corner portion 111a by a third distance (dq3), and are non-corner regions (AT). The first and second outermost pad portions (140a2, 140b2) disposed in the position are separated from the end of the solar cell by a fourth distance (dq4).

  Preferably, the third distance (dq3) and the fourth distance (dq4) are substantially the same, and the distance is 5-15 (mm).

  In this embodiment, since the first and second outermost pad portions are located at the same distance from the end or corner portion 111a of the solar cell, unlike the third embodiment, the first and first outer pads 2 The outermost pad portions are not located on the same line. Therefore, since the end of the wiring material is fixed in accordance with the first and second outermost pad portions, it is positioned in the first wiring material 125a located in the corner area (AC1, AC2) and in the non-corner area (AT). The second wiring member 125b should be cut separately, but conversely, the bonding force of the wiring member can be increased.

  When connecting two adjacent solar cells, the wiring member should be connected to the front surface and the rear surface, respectively, and should be warped where the two solar cells are adjacent. By the way, since the wiring material is made of a metal material as described above, physical stress occurs when warped, and the wiring material is exposed to high temperature during the modularization process and overlaps with the thermal stress. The bonding strength between the solar cell and the solar cell is reduced.

  By the way, it has been experimentally found that when the wiring member is separated from the end of the solar cell by about 5-15 (mm) and attached to the outermost pad portion, the binding force is increased. Therefore, in this embodiment, in consideration of such points, the first and second outermost pad portions (140a, 140b) are formed by dropping by 5-15 (mm) to improve the coupling force of the wiring material. Let If the distance is less than 5 (mm), the coupling force is rather reduced, and if it is greater than 15 (mm), there is a problem that the power generation area of the solar cell is reduced.

  In the above embodiment, the embodiment of the present invention has been described based on the double-sided light receiving solar cell. Hereinafter, an embodiment of the present invention using a rear contact solar cell in which all electrodes are located on the rear surface of the solar cell will be described.

  FIG. 20 shows an overall state of a solar cell module configured using a back contact solar cell in another embodiment of the present invention, and FIG. 21 shows a cross-sectional state of the solar cell.

  In this embodiment, each of the solar cells 10 has a cubic shape with a thin thickness, and the first electrode 11 collects electrons and holes separately on one surface (for example, the rear surface of the substrate). And the second electrode 13 is formed.

  The first electrode 11 and the second electrode 13 are elongated in the vertical direction and are arranged in parallel with the adjacent ones. Moreover, the 1st electrode 11 and the 2nd electrode 13 are alternately arranged by the horizontal direction, and are spaced apart and adjoined by the fixed distance.

  The first electrode 11 and the second electrode 13 are electrically connected to a wiring member 25 and are connected to the second electrode 13 or the first electrode 11 of another adjacent solar cell.

  The wiring member 25 is arranged in the lateral direction intersecting the length direction of the electrodes (11, 13), and two adjacent solar cells are connected in series.

  As described above, the wiring member 25 includes a core layer made of a metal having good conductivity and a coating layer made of a solder substance. In this embodiment, the wiring member 25 preferably has a rectangular strip shape with a small thickness, the cross-sectional appearance of the wiring member 25 is rectangular, and the line width is 1-2 (mm). The thickness is 50-150 (μm). The wiring material of this embodiment can also have a wire shape as described above. In this embodiment, since the solar cell has a rear surface contact type structure, the wiring member is located on the rear surface of the solar cell. Therefore, since the light receiving surface is not reduced by the wiring material, the wiring material is configured to have a thin plate material shape in this way to increase the area in contact with the electrode and to increase the coupling force between the electrode and the wiring material. .

  In this embodiment, the wiring member 25 includes a first wiring member 21 and a second wiring member 23. The first wiring member 21 is physically and electrically connected to the first electrode 11 of the second solar cell 10b disposed in the center, and the other is connected to the second electrode 13 of the third solar cell 10c. The second solar cell 10b and the third solar cell 10c are connected in series by being physically and electrically connected. The second wiring member 23 is physically and electrically connected to the second electrode 13 of the second solar cell 10b disposed at the center, and the other is the first electrode of the first solar cell 10a. 11, the second solar cell 10b and the first solar cell 10a are connected in series.

  Based on a solar cell having a size of 160 (mm) * 160 (mm), 12-18 first wiring members 21 and second wiring members 23 are used and connected to two adjacent solar cells. The

  The first wiring member 21 and the second wiring member 23 are alternately arranged in the vertical direction, and are arranged in parallel with the adjacent ones.

  By arranging the wiring member 25 in the direction intersecting with the electrodes (11, 13) in this way, it becomes easy to connect the wiring member 25 to the electrodes (11, 13), and the electrodes (11, 13). ) And the wiring member 25 are easily aligned. In this embodiment, the first electrode 11 and the second electrode 13 are all arranged so as to be parallel to the rear surface, and the wiring member 25 is connected in a direction intersecting with the first electrode 11 and the second electrode 13. The thermal deformation direction of the material 25 and the thermal deformation direction of the electrodes (11, 13) intersect to protect the solar cell from potential stress caused by the thermal deformation.

  In such an embodiment, any one wiring member 25 with the first electrode 11 from the intersection 41 where any one wiring member 25 with the first electrode 11 intersects via the conductive adhesive portion. The second electrode 13 and the other wiring member can be connected via the conductive adhesive portion from the intersection 41 where the second electrode 13 and the other wiring member 25 intersect with each other.

  Furthermore, another wiring material connected to the second electrode 13 can be insulated from the first electrode 11 from the intersection 41 intersecting the first electrode 11 via the insulating adhesive portion. Any one wiring member connected to the second electrode 13 can be insulated from the second electrode 13 from the intersection 41 intersecting the second electrode 13 through the insulating adhesive portion.

  Here, the conductive adhesive part is made of a conductive paste (solder paste) containing solder such as lead (Pb) or tin (Sn), epoxy (epoxy) synthetic resin or silicon synthetic resin. Can be any one of the conductive adhesives. When such a conductive adhesive portion is melted, the wiring material can be selectively connected to the first electrode 11 or the second electrode 13 through soldering for joining the two base materials.

  Furthermore, the insulating adhesive portion can be formed of an epoxy-based synthetic resin, a silicon-based synthetic resin, or a ceramic material, and the wiring member 25 is connected to the first electrode 11 or the second electrode through such an insulating adhesive portion. 13 is selectively insulated.

  In FIG. 20, a point indicated by an intersection 41 indicates a contact point where the wiring member 25 and the electrodes (11, 13) are connected. According to this contact point, the conductive layer and the solder paste described above are formed, The wiring material is soldered.

  As illustrated in FIG. 21, in this embodiment, the solar cell 10 has a rear contact type structure in which all of the first electrode 11 and the second electrode 13 are located on the rear surface of the semiconductor substrate 15.

  The semiconductor substrate 15 forms a pn junction, and light reflection prevention or reflection suppression and passivation (passivation) are performed on a front surface (a surface on which light is incident) and a rear surface (a surface opposite to the front surface) of the semiconductor substrate 15, respectively. ) Thin films (16, 17) responsible for the function are formed.

  And between the 1st electrode 11 and the semiconductor substrate 15, and between the 2nd electrode 13 and the semiconductor substrate 15, the emitter 18 and the back surface electric field part 19 are each formed in thin thickness, and an electrode (11 , 13) so that charges can be well collected in the direction of 13).

  On the other hand, in the solar cell module shown in FIG. 20 described above, two solar cells adjacent to each other are connected. However, as shown in FIG. 22, the wiring member is connected only to each solar cell, and two adjacent solar cells can be connected to each other by a connector (CN).

  More specifically, in the second solar cell 10b, the first wiring member 211 is connected to the first electrode 11, and the second wiring member 231 arranged adjacent to and parallel to the second electrode 13 is connected. In the third solar cell 10c, the first wiring member 211 is connected to the second electrode 13, and the second wiring member 231 disposed adjacent to and parallel to the second electrode 13 is connected to the first electrode 11. Yes.

  And the 1st wiring material 211 protrudes toward the 3rd solar cell 10c from the 2nd solar cell 10b, and the 1st wiring material 211 protrudes toward the 2nd solar cell 10b also in the 3rd solar cell 10c. The two are overlapped between the second solar cell 10b and the third solar cell 10c.

  The connector (CN) is long in the direction intersecting the first wiring member 211, and is physically and electrically connected to the first wiring member 211 that is positioned and overlaps between the second solar cell 10b and the third solar cell 10c. Connected to. In a preferred embodiment, the connector (CN) is made of a wiring material or made of a conductive metal material, and is physically connected to the first wiring material 211 via the solder paste, conductive layer, or soldering described above. Electrically connected.

  Since the first solar cell 10a and the second solar cell 10b are also connected by a connector in the same manner, detailed description thereof is omitted.

  Hereinafter, the wiring material of the solar cell module shown in FIG. 20 will be described with reference to FIG. FIG. 23 shows a plan view in which two adjacent solar cells in the solar cell module of FIG. 20 are connected by a wiring material.

  In FIG. 23, the first solar cell (CE1) and the second solar cell (CE2) are connected by the first wiring member 21. The first wiring member 21 is connected to the first electrode 11 of the first solar cell (CE1), and is connected to the second electrode 13 of the second solar cell (CE2).

  A second wiring member 23 is located between the first wiring member 21 and the first wiring member 21, and the second wiring member 23 is another solar cell adjacent to the wiring member in the length direction (see FIG. (Not shown).

  The first wiring member 21 has a corner wiring member (21a) located in the corner region (AC1) including the corner portion 111a and a non-corner located in the non-corner region (AT) where the corner portion 111a is not present, depending on the position. The wiring material 25b can be divided.

  One end 21a ′ of the corner wiring member 21a is located at the lower corner portion (111a_dw) of the first solar cell (CE1), and the other end (2 ″) is the upper corner portion of the second solar cell (CE2). It is located at (111a_up).

  Since the corner wiring material 21a is formed up to the corner portion in this way, all the first electrodes 11 belonging to the corner region (AT) and the corner wiring material 21a are connected to increase the charge collection efficiency.

  Similarly, one end 21b ′ of the non-corner wiring member 21b is located at the end of the first solar cell (CE1), and the other end 21b ″ is located at the end of the second solar cell (CE2). Therefore, since all the first electrodes 11 belonging to the non-corner region (AT) are connected to the non-corner wiring member 25b, the charge collection efficiency can be increased.

  On the other hand, when the end of the wiring member 25 is positioned in the same manner as the end of the solar cell in this way, the wiring member 25 is easily separated from the solar cell, so that the pad portion 140 corresponds to the end of the wiring member. Can be further formed.

  The pad portion 140 increases the area of the electrode that meets the end of the wiring member 25 so that the wiring member is not separated. The pad unit 140 may be formed of the same material as the electrode or may be formed of a separate material different from the electrode.

  Between the pad part 140 and the wiring material, the above-described solder paste or conductive layer is positioned so that the wiring material is firmly attached to the pad part 140. Alternatively, the wiring material can be soldered to the pad portion 140.

  In the above description, the case where the solar cell includes a corner portion has been described as an example. However, the above-described embodiment is similarly applied to a general solar cell in which the planar shape without the corner portion is a quadrangle. Can do.

  Further, an example of the solar cell corner portion (AC1) in the solar cell module described with reference to FIG. 22 will be described more specifically with reference to FIG.

  FIG. 24A is an enlarged view of a part of the front surface of the solar cell module described in FIG. 22, and FIG. 24B is an enlarged view of a part of the rear surface of the solar cell module described in FIG. It is an enlarged view.

  24A and 24B, the first wiring member 211 is connected to the first electrode 11 of each solar cell (CE1, CE2), and the second wiring member 231 is connected to each solar cell (CE1). , CE2) can be connected to the second electrode 13.

  Further, the first wiring member 211 of the first solar cell (CE1) and the second wiring member 231 of the second solar cell (CE2) are commonly connected to the connector (CN), and the first solar cell (CE1). The second solar cells (CE2) can be connected in series with each other.

  Furthermore, the first and second wiring members (211 and 231) connected to the solar cells (CE1 and CE2) are as shown in FIGS. 24A and 24B in order to further increase the carrier transmission efficiency. The solar cell (CE1, CE2) can also be positioned at the corner (AC1).

  At this time, as shown in FIGS. 24A and 24B, when two adjacent solar cells are connected to each other by the connector (CN), the corner portion (AC1) of the first solar cell (CE1) is connected. The length (211A) of the connected first wiring member 211 protruding out of the first solar cell (CE1) is the second wiring member 231 connected to the corner portion (AC1) of the second solar cell (CE2). May differ from the length (231B) protruding out of the second solar cell (CE2).

  That is, as shown in FIG. 24B, the first wiring member 211 connected to the first solar cell (CE1) is directed toward the second solar cell (CE2), and the semiconductor substrate of the first solar cell (CE1). The length (211A) protruding outside is that the second wiring member 231 connected to the second solar cell (CE2) faces the first solar cell (CE1) outside the semiconductor substrate of the second solar cell (CE2). The protruding length (231B) may be different from each other.

  Thus, in the solar cell module according to the present invention, when the first wiring member 211 and the second wiring member 231 of two solar cells adjacent to each other by the connector (CN) are electrically connected to each other, The first and second wiring members (211 and 231) are also positioned at the corner (AC1), but the protruding lengths (211A and 231B) of the first and second wiring members (211 and 231) are set. The tips of the first and second wiring members (211, 231) may be positioned so as to be superimposed on the connectors (CN) in different ways, respectively, while making the manufacturing process of the solar cell module easier, The efficiency of the battery module can be further improved.

Claims (31)

A plurality of solar cells each including a first electrode for collecting a first conductive charge and a second electrode for collecting a second conductive charge opposite to the first conductive charge and arranged adjacent to each other When,
A plurality of wiring members electrically connected to the second electrode of the adjacent solar cell and arranged in parallel with each other;
The plurality of wiring materials are:
A solar cell comprising: a first wiring member disposed in a corner region of a solar cell including a corner portion having a curved end; and a second wiring member disposed in a non-corner region of the solar cell excluding the corner region. module.   The solar cell module according to claim 1, wherein a length of the first wiring member is shorter than a length of the second wiring member.   2. The solar cell module according to claim 1, wherein a total number of first electrodes and second electrodes connected to the first wiring member is less than a total number of first electrodes and second electrodes connected to the second wiring member. .   The end of the first wiring material is separated from the corner portion by a first distance, and the end of the second wiring material is separated from the end of the solar cell by a second distance. Solar cell module.   The solar cell module according to claim 4, wherein the first distance and the second distance are the same.   The solar cell module according to claim 5, wherein the first distance is smaller than a pitch between adjacent first electrodes.   The solar cell module according to claim 4, wherein the first distance is shorter than the second distance.   2. The solar cell module according to claim 1, wherein the first electrode is located on a front surface of each of the plurality of solar cells, and the second electrode is located on a rear surface of each of the plurality of solar cells.   The solar cell module according to claim 8, wherein an electrode pad portion is formed at a portion where the first electrode and the plurality of wiring members intersect or a portion where the second electrode and the plurality of wiring members intersect.   2. The solar cell module according to claim 1, wherein the first electrode and the second electrode are located on a rear surface of each of the plurality of solar cells. In a portion where the plurality of wiring members electrically connected to the first electrode and the first electrode intersect, a conductive adhesive portion is formed,
The solar cell module according to claim 10, wherein an insulating adhesive portion is formed at a portion where the plurality of wiring members electrically connected to the first electrode and the second electrode intersect.   2. The plurality of wiring members connected to the second electrode of the adjacent solar cell and the plurality of wiring members connected to the first electrode are connected to each other via a connection bar. Solar cell module.   The solar cell module according to claim 12, wherein the connection bar is located between the adjacent solar cells.   The connection bar extends in a direction intersecting with a length direction of the plurality of wiring members connected to the second electrode and a length direction of the plurality of wiring members connected to the first electrode. 12. The solar cell module according to 12. The non-corner region of the solar cell is located at the center of the semiconductor substrate of the solar cell, the corner region of the solar cell is located on both sides of the non-corner region of the semiconductor substrate,
2. The solar cell module according to claim 1, wherein a length of the semiconductor substrate in the corner region is shorter than a length of the semiconductor substrate in the non-corner region.   The solar cell module according to claim 1, wherein at least one wiring member connected to the first electrode and at least one wiring member connected to the second electrode are located in the corner region.   The solar cell module according to claim 1, wherein each of the plurality of wiring members is formed of a wire having a circular cross section.   2. The solar cell module according to claim 1, wherein each of the plurality of wiring members is formed of a ribbon having a rectangular cross section.   The first electrode that exists between the end of the second wiring member and the end of the solar cell and is not connected to the first wiring member or the second wiring member is connected to the second wiring member by a connection bar. The solar cell module according to claim 7, which is connected to one electrode. A plurality of first pad portions arranged at intersections of the first electrode and the first wiring member in the corner region;
The non-corner region further includes a plurality of second pad portions disposed at intersections of the first electrode and the second wiring member,
An end of the first wiring member is fixed to an outermost pad portion located closest to an end of the solar cell among the plurality of first pad portions, and an end of the second wiring member is fixed to the plurality of second pads. The solar cell module according to claim 1, wherein the solar cell module is fixed to an outermost pad portion located closest to an end of the solar cell in the pad portion.   The first outermost pad portion to which the first wiring material is fixed is separated from the corner portion by a third distance, and the second outermost pad portion to which the second wiring material is fixed is the solar cell. The solar cell module according to claim 20, wherein the solar cell module is separated from the end by a fourth distance.   The solar cell module according to claim 21, wherein the third distance is the same as the fourth distance.   The solar cell module according to claim 22, wherein each of the third distance and the fourth distance is 5 to 15 (mm).   The solar cell module according to claim 21, wherein the third distance is shorter than the fourth distance.   The solar cell module according to claim 21, wherein the first outermost pad portion and the second outermost pad portion are located on the same line with reference to the extending direction of the first electrode.   The solar cell module according to claim 20, wherein the plurality of first pad portions are connected to each of the plurality of connection electrodes, and the plurality of second pad portions are connected to each of the plurality of connection electrodes.   27. The solar cell module according to claim 26, wherein the plurality of connection electrodes are connected to all of the first electrodes existing in each of the corner region and the non-corner region.   The solar cell module according to claim 23, wherein the connection electrode connects at least one first electrode existing between the outermost pad portion and an end of the solar cell to the outermost pad portion.   And a link electrode configured to extend in a diagonal direction and connecting at least one first electrode existing between the outermost pad portion and an end of the solar cell to the outermost pad portion. Item 23. The solar cell module according to Item 22.   The first wiring member includes a plurality of first wiring members, the second wiring member includes a plurality of second wiring members, and the number of the plurality of second wiring members is the number of the plurality of first wiring members. The solar cell module according to claim 1, wherein the solar cell module is at least 5 times more.   27. The solar cell module according to claim 26, wherein each of the plurality of wiring members is located at the center of each region partitioned by the width of the solar cell, with the total number of the plurality of wiring members being divided.

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